The present invention relates to a distributing apparatus and particularly to an apparatus which is designed to divide or split a single stream of a two-phase flow, for example, vapor liquid into a plurality of individual streams with minimum pressure loss in which each of the individual streams has substantially the desired ratio of vapor to liquid. In many processes a main flow of vapor liquid must be divided or split into several individual streams while maintaining the desired liquid to vapor ratio in the individual streams. For example, a central power plant or furnace may be used to supply process heat in the form of steam to several individual processes or locations. It is necessary that the main steam flow be divided into several individual flows to supply the individual locations. It is obvious that one must maintain the desired ratio of vapor to liquid in each of the individual flows or the individual flows located the greatest distance from the source will consist primarily of water and very little steam. Also, the distribution must conform to a desired pattern and not produce abnormalities or variations.
The problem is more acute in thermal recovery projects where steam is being injected into hydrocarbon bearing formations to increase the production. In these systems it is very common to use low quality steam, for example, 80% quality steam. The practice of using low quality steam is necessitated by the need to utilize low quality or brackish waters in the generation of the steam. To prevent the salts and other minerals from depositing on the steam generator tubes, it is necessary to retain part of the flow in a liquid state in order to maintain the salts and other impurities in solution. If it is necessary to distribute this low quality steam to several individual injection wells from one large pipeline, the problem that arises is one of dividing the main flow into the individual flows with minimum pressure loss while maintaining the desired ratio between vapor and water in the individual flows.
The above problem of thermal recovery projects will become even more acute when large cogeneration plants are installed. The cogeneration plants will produce both electricity and the steam required for the thermal recovery process. These plants will be centralized and the initial steam flow for thermal recovery will be large and must be divided into the individuals flows for individual wells. These centralized plants will require that the initial distribution of steam will be through large diameter main flowlines with minimum pressure loss.
The common practice is to use tee convections to split the main flow into separate streams. It is possible using properly designed tees to split the main flow and maintain the desired vapor liquid ratio. While the vapor liquid ratio is maintained the pressure loss in a tee is high. The pressure loss results from the loss of inertia in the liquid as it flows through the tee.
In the prior art, for example, U.S. Pat. No. 3,899,000, it is suggested that a liquid vapor mixture could be separated into two or more individual flows by use of a closed vessel. The vessel is mounted vertically and provided with a top inlet and two bottom outlets. A flat horizontal baffle is used to divert the inlet flow from the open ends of the outlets. The axis of the inlet and the axis of the outlets are substantially parallel so the flow of the liquid vapor is axially through an elongated vessel. The liquid vapor ratio is maintained by utilizing the outlets as standpipes and the vessel as a reservoir. Once sufficient liquid collects in the bottom of the vessel, it can overlow the top of the outlets and liquid will be added to the vapor flowing out of the outlets. While this system may be satisfactory it does rely upon the condensing of the liquid, separating it from the vapor and then recombining it with the vapor. This is an inefficient way to separate the main stream into the individual streams and results in a loss of overall energy from the system. Also, an equal amount of water will be added to each standpipe regardless of its size and the vapor liquid ratio may not be the same in each outlet depending on the sizes of the individual outlets.